Olive-gray vat dye.



UNITED STATES PATENT OFFICE.

WALTER MIEG, OF ELBERFELD, GERMANY, ASSIGNORMIO FARBENFABRIKEN VORM. FRIEDR. BAYER & 00., 0F ELBERFELD, GERMANY, A CORPORATION OF GERMANY.

OLIVE-GRAY VAT DYE.

No Drawing.

To all whom it may concern:

Be it known that I, WALTER Mine, doctor of philosophy, chemist, citizen of the German Empire, residing at Elberfeld, Germany, have invented new and useful Inipro'vements in Olive-Gray Vat Dye,' of which the following is a specification.

The present invention relates to the manufacture and production of a new vat dye which dyes cotton from an alkaline hydrosulfite vat fast olive-gray shades.

The process for producing the new dye consists in treating dibenzoyl para para diamino alpha alpha dianthrimid, (produced by condensing l-benzoylamino-4- chloroanthraquinon with monobenzoyl-1.4-

diaminoa'nthraquinon according to U. 8.,

Letters Patent No. 971,224), with concentrated sulfuric acid. The process proceeds most probably according to the following equation:

NH COC6H& NIT-COCsHs NH CO (Y I (Y 'f Ago H--COU5II5 I-LUDCsHt In order to illustrate the new process more fully the following example is given, the parts being by weight-'1. part of dibeuzoyl para para diamino alpha 1 alpha- V dianthrimid (produced by condensing 1- benzoylamino 4 chloroanthraquinon with nionobenzoyl 1.4 diaminoanthraquinon according to British Letters Patent No. 25986/09) is"heated while stirring with 10 parts of sulfuric acid (66 B.) to 30"':' 5 C.

Specification of Letters Patent. Pate t d June 27, 1911. Application filed January 24, 1911. Serial No. 604,437.

until the mass has assumed a brown c0ld'ration. 10 parts of a 40 er cent. fuming sulfuric acid are then ad ed and the mixture is poured on ice. The dye separates in the shape of olive-green flakes, it is filtered ofl and washed with Water. It is a dark pow der which is soluble in concentrated suli'uric acid with a cherry red color and only difficulty soluble in a boiling or anic solvent, such as quinolin with an o ive-green coloration.

I claim:

The herein described new dye having probably the formula:

which dye is after being dried and pulverized a" dark powder soluble in concentrated sulfuric acid with a cherry red coloration; and dyeing cotton from an alkaline hydro sulfite vat fast olive-gray shades, substantially as described.

In testimony whereof I have hereunto set my hand in the presence of two subscribing witnesses.

WALTER MIEG. [1,. 8.] Witnesses:

CHAS. J. WRIGHT, ALFRED HENKEL. 

